Call it the ultimate in military logistics. As land routes from Pakistan into Afghanistan are cut, sabotaged or otherwise interrupted, the U.S. military has developed alternative railroad routes that make the Orient Express look like a branch line.
They are called — rather prosaically — the Northern Distribution Network, or NDN. The main route begins at the port of Riga in Latvia, from where freight trains roll across Russia, and continues along the edge of the Caspian Sea. It crosses the deserts of Kazakhstan and into Uzbekistan. About 10 days after beginning their odyssey, the containers cross into Afghanistan, carrying everything from computers and socks to toilet paper and bottled water.
Source: To Afghanistan, on the slow train, Tim Lister, CNN, 29 November 2011